Bag machine



Jan. 2, 1968 c. M. SCHOTT, JR 3,361,614

BAG MACHINE Filed Feb. 8, 1965 -9/ a 0 f9 i n g I f Ii 11 E1, 1

United States Patent 3,361,614 BAG MACHINE Charles M. Schott, Jr., Gloucester, Mass., assignor to Gloucester Engineering Co., Inc., Gloucester, Mass., a corporation of Massachusetts Filed Feb. 8, 1965, Ser. No. 430,804 4 Claims. (Cl. 156-583) This invention is a continuation-impart of my co-pending application Ser. No. 251,327, filed Jan. 14, 1963, entitled, Machine for Altering Moving Webs, now Patent No. 3,322,604, and has in general the same obiects. In particular, an object of the present invention is to produce severed bags or deliver segments of webs intermittently from a continuously moving web source, or more generally to provide a unique means for synchronized acting upon a web while having either the input or output continuous and the other intermittent.

In this embodiment, rather than a double rolled shuttle, a single rolled shuttle is employed, and synchronized therewith is an intermittent device that maintains tension on the web, and moves it intermittently.

In the drawings:

Referring to FIGS. 1-3, the driving belt 21 is trained through a loop similar to that of FIGS. 1 or of the parent application mentioned above, to which reference is made.

Referring to FIGS. 1 and 2, the web 13 after being formed into a loop about shuttle roll 4, and passing under the reciprocal altering device 24a does not loop around the second shuttle roll 6, but rather it extends across the top of that roll to a pair of rolls 87 and 89 that form a nip. The web proceeds through this nip to a cutting head 91 at which the web is periodically cut into separated pieces.

It will be understood, from the teachings of the parent application, that when the shuttle roll 4 proceeds in the direction to the right at one half the speed at which the web is being fed to the machine at roll 8, the web extending from shuttle roll 4 across roll 6 to the nip 87, 89 is stationary, and at that time the cutting head can be actuated by mechanism 93 to cut the stationary web. Then when the shuttle roll proceeds in the direction to the left, to return to its initial position, the film extending from shuttle roll 4 to cutting head 91 moves rapidly, being pulled by the pair of rolls 87, 89, causing the next section of web to move past the cutting head until the shuttle again reverses direction.

It is, however, essential that the roll nip 87 and 89 be driven in direct relation to the action of the shuttle. For this purpose the timing belt 21 is trained about both shuttle rolls 4 and 6 so that the part of the belt extending between shuttle rolls 4 and 6 at all times corresponds exactly in surface speed to that of the film, stopping when the shuttle moves to the right and moving very fast when the shuttle moves to the left. A sprocket wheel 85 is driven by this span of belt, between shuttle rolls 4 and 6, and two idler pulleys 85' and 85" are provided to maintain the timing belt engaged with sprocket 85, and to keep the belt parallel to the direction of movement of the shuttle as it approaches and leaves sprocket wheel 85, these details being shown in FIG. 3. Referring to FIG. 1, second and third timing belts 21' and 21" are driven by sprocket 85 and in turn drive roll 87, thus making the surface speed of the roll 87 exactly correspond to the speed of the film produced by the shuttle rolls, stopping and starting in synchronization. The top roll 89 can be very light in weight, and driven only through the frictional contact, as shown, or it can be driven by roll 87 through a separate driving belt, not shown.

The position of the cutting head 91 relative to the roll 6 can be varied along slide 103 when the distance between cuts is to be varied and the mechanism 93 that actuates the cutting head 91 can be driven by the same means that actuate altering device 24a.

In this embodiment the reciprocating die is not actuated directly by a cam, but rather through a hydraulic link. Referring to FIG. 1, cam 26a turned at a speed dependent upon that of the arriving film actuates valve 28a which opens and closes single acting piston 16a to a source of pressurized hydraulic fluid 32a. When opened to the fluid, the piston 16a moves to the left, against the action of the spring, pressing the die against the web. When closed, the fluid drains out and spring 16b returns the die. One particular advantage of this arrangement is that the pressure exerted by the die can be regulated by changing the setting of the relief valve without having to change the form of the cam 26a.

Also, by regulating the speed of the pump the time elapsed during downward travel of the die, relative to the time of the entire cycle, can be varied, thereby giving a control for the time the die engages the film.

It Will be understood that the web can be fed into the machine continuously while separated bags are moved out of the machine at intervals corresponding to the frequency of operation of the shuttle.

More generally, it will be appreciated that by synchronizing a web locking device with a single shuttle roll, and operating upon the web in between these devices, particularly in combination with hydraulic control, provides an improved means of operating upon plastic webs.

What is claimed is:

1. A machine for periodically imparting a formation to a web as the web is fed continuously to the machine, the machine having guiding means defining a web path, forming means adapted to impart a formation to said web, at least one guiding member preceding said forming means, the continuously moving web trained about said guiding member to form a loop having substantially parallel legs, said guiding member mounted on a movable carrier for reciprocation in a path substantially parallel to said legs to alternately take up and pay out said web, said guiding member adapted to move in the take-up direction while said web is stopped relative to said forming means, web locking and pulling means located beyond said guiding member synchronized to lock said web with movement of said guiding member in the take-up direction, and to pull said web during movement of said guiding member in the pay-out direction, thereby adapted to produce a discontinuous output, said web locking and pulling means comprising a pair of rolls forming a nip, a drive train comprising said movable carrier for said guiding member, an endless belt so associated with said carrier member that a portion of the belt can stop and start interdependently with the take-up and pay-out movements of said guiding member, and a drive linkage so associated with said portion of said belt and said pair of nip rolls that said nip rolls can lock and pull interdependently with the take-up and pay-out movements of said guiding member, and means to impart drive forces to said drive train to start and stop said web.

2. The machine of claim 1 wherein said means to impart drive forces to said drive train comprises a hydraulic motor adapted to move intermittently to start and stop said web.

3. The machine of claim 2 wherein said hydraulic motor comprises a hydraulic piston drivingly connected to said carrier member and adapted to be forced back and forth within a hydraulic cylinder.

4. In combination a frame means mounted for oscillating movement, a multiplicity of axles mounted on said frame means for movement therewith, at least one web engaging roll mounted on one of said axles, web guide means adapted to deliver a web to said roll in a first path substantially parallel to the movement of said roll, forming means arranged to receive said Web from the opposite side of said roll in a path substantially parallel to said first path, means arranged to drive said frame means in oscillating movement to cause said web to stop relative to said forming means vperiodically, sprocket means mounted on a pair of said axles, a timing belt means mounted to travel over both of said sprockets and having a section thereof whose movements and stops correspond to those of said Web at said forming means, power take-off means powered by said section of timing belt, adapted to control the operation of a second mechanism in synchronism with the movement of 5 said web, said second mechanism comprising a pair of nip rolls arranged to receive said web, said nip rolls positioned to move said web relative to said forming means.

References Cited UNITED STATES PATENTS 501,603 7/1893 Honiss 83-235 2,652,879 9/1953 Keller et al 156-583 2,667,924 2/1954 Dutro 83-113 10 3,084,841 4/1963 Hata et a1. 226-113 FOREIGN PATENTS 578,542 5/1924 France.

DOUGLAS 1. DRUMMOND, Primary Examiner. 

1. A MACHINE FOR PERIODICALLY IMPARTING A FORMATION TO A WEB AS THE WEB IS FED CONTINUOUSLY TO THE MACHINE, THE MACHINE HAVING GUIDING MEANS DEFINING A WEB PATH, FORMING MEANS ADAPTED TO IMPART A FORMATION TO SAID WEB, AT LEAST ONE GUIDING MEMBER PRECEDING SAID FORMING MEANS, THE CONTINUOUSLY MOVING WEB TRAINED ABOUT SAID GUIDING MEMBER TO FORM A LOOP HAVING SUBSTANTIALLY PARALLEL LEGS, SAID GUIDING MEMBER MOUNTED ON A MOVABLE CARRIER FOR RECIPROCATION IN A PATH SUBSTANTIALLY PARALLEL TO SAID LEGS TO ALTERNATELY TAKE UP AND PAY OUT SAID WEB, SAID GUIDING MEMBER ADAPTED TO MOVE IN THE TAKE-UP DIRECTION WHILE SAID WEB IS STOPPED RELATIVE TO SAID FORMING MEANS, WEB LOCKING AND PULLING MEANS LOCATED BEYOND SAID GUIDING MEMBER SYNCHRONIZED TO LOCK SAID WEB WITH MOVEMENT OF SAID GUIDING MEMBER IN THE TAKE-UP DIRECTION, AND TO PULL SAID WEB DURING MOVEMENT F SAID GUIDING MEMBER IN THE PAY-OUT DIRECTION, THEREBY ADAPTED TO PRODUCE A DISCONTINUOUS OUTPUT, SAID WEB LOCKING AND PULLING MEANS COMPRISING A PAIR OF ROLLS FORMING A NIP, A DRIVE TRAIN COMPRISING SAID MOVABLE CARRIER FOR SAID GUIDING MEMBER, AN ENDLESS BELT SO ASSOCIATED WITH SAID CARRIER MEMBER THAT A PORTION OF THE BELT CAN STOP AND START INTERDEPENDENTLY WITH THE TAKE-UP AND PAY-OUT MOVEMENTS OF SAID GUIDING MEMBER, AND A DRIVE LINKAGE SO ASSOCIATED WITH SAID PORTION OF SAID BELT AND SAID PAIR OF NIP ROLLS THAT SAID NIP ROLLS CAN LOCK AND PULL INTERDEPENDENTLY WITH THE TAKE-UP AND PAY-OUT MOVEMENTS OF SAID GUIDING MEMBER, AND MEANS TO IMPART DRIVE FORCES TO SAID DRIVE TRAIN TO START AND STOP SAID WEB. 